1. Garbage In, Garbage Out. A reference to the fact that computers, unlike humans, will unquestioningly process the most nonsensical of input data and produce nonsensical output. Of course a properly written program will reject input data that is obviously erroneous but such checking is not always easy to specify and is tedious to write.

GIGO is usually said in response to users who complain that a program did not "do the right thing" when given imperfect input or otherwise mistreated in some way. Also commonly used to describe failures in human decision making due to faulty, incomplete, or imprecise data.

2. Garbage In, Gospel Out. This more recent expansion is a sardonic comment on the tendency human beings have to put excessive trust in "computerised" data.

see also KIBO


This article (or an earlier version of it) contains material from FOLDOC, used with permission.